Is Objective-J essentially JavaScript?

I've been stumbling upon Objective-J. It should be a superset of JavaScript ... but how's that possible without a browser plugin or some addon? How can they drive around the 开发者_运维问答syntax of JavaScript and make it look like Objective-C code? I mean... COOL... but I don't get it ;) Must I compile that Objective-J code before it goes to the browser?

According to the Wikipedia article on Objective-J:

Programs written in Objective-J need to be preprocessed before being run by a web browser's JavaScript virtual machine. This step can occur in the web browser at runtime or by a compiler which translates Objective-J programs into pure JavaScript code. The Objective-J compiler is written in JavaScript, consequently deploying Objective-J programs does not require a plugin attached to the web browser.

“Must I compile that Objective-J code before it goes to the browser?”

Nope.

All programming languages are written in another programming language. (E.g. Python — or the main implementation, anyway — is written in C.)

Objective-J is written in JavaScript, hence it can run entirely in the browser.